Can you plate iron or magnesium onto copper in a galvanic cell?

[z.js]

I was thinking of plating iron or magnesium on to copper with a galvanic cell. Would this work?

3Cu(s) + 2Fe²⁺(aq) --> 3Cu²⁺(aq) + 2Fe(s)
Cu(s) + Mg²⁺(aq) --> Cu²⁺(aq) + Mg(s)

In the cathode, when the Cu turns into Cu²⁺ and makes Cu(OH)₂, of what use is it? And in the anode, when the O^2- makes water with H⁺, of what use is the OH^- that's left?

 

[z.js]

? :(

 

[Borek]

It won't work by itself, you need electroplating (with external source of current).

In general there is no use of byproducts.

Judging from the way you asked the question and from the drawing you should start with a general chemistry textbook to get a grasp of what it is all about, then go for some electroplating handbook for recipes.